Since we work from home, AI files are stored on the google drive. After a colleague has changed a file, there are suddenly many more layers in it. It looks like these are automatically generated. Texts pulled apart, some layers with only a single punctuation mark. How can this be fixed? I work on a Windows computer and my colleague on an Apple.
Has the colleague perhaps changed the file to a pdf, or edited it in something other than Illustrator? It's difficult to tell much without seeing the file — is it possible for you to share it? And do you have a copy of the unaltered file?
In addition to what Peter keenly saw and said, your asking in the first place makes me believe that your company may lack proper backup/rescue measures; unless of course you can just go back to the latest sound version, and the latest version by your hand.
If that is the case, until such measures are in place, you may build an emergency service for files you (co)work with by saving sound versions differently and under different names, on your own harddisk and preferably also externally.
Apart from the benefit to your company, such a temporary service may also help defend your work, and sanity.